Adverse Effects if Advancement in Technology!!

On taking a cell phone apart, one would find a few individual parts, such as, an antenna, a liquid crystal display (LCD), a keyboard, a microphone, a speaker, and a battery. Inside the phone there is a circuit board which is otherwise called the heart of the system. First you would enter in room analog-to-digital and digital-to-analog conversion chips which translate the outgoing audio signal from analog to digital and the incoming signal from digital back to analog. It can process millions of calculations per second in order to compress and decompress the voice stream. Then you would enter into the second room where the digital signal processor (DSP) is located.

Here in this room you would soon discover that the DSP is a highly customized processor designed to perform signal manipulation calculations at high speed. Next, you would enter the third room with the microprocessor. The microprocessor handles all the main functions for the keyboard and display, deals with command and control signaling with the base station (cell tower) and also coordinates the rest of the functions on the board. The read only memory (ROM) and Flash memory chips provide storage for the phone’s operating system and customization features, such as the phone directory.

The radio frequency (RF) and power section handles power management and recharging, and also deals with the hundreds of FM channel. Finally, the RF amplifiers handle signals traveling to and from the antenna.
An analog signal has a base carrier’s radio frequency signal, which is modified in some way to amplify the strength of the signal or vary the frequency to add information to the signal. An analog signal can be represented as a series signal to a signal carrier known as sine waves because carrier waves are analogous to the fluctuations of the human voice or other sound that is being transmitted. Advanced Mobile Phone System (AMPS), the first common cell phone system in the U.S., uses a range of frequencies between 824MHz and 894 MHz for analog cell phones. A Hertz (Hz) is equal to cycles per second, while a MegeHertz (MHz) is equal to one million cycles per second.

The frequencies chosen to be used in analog voice channels are 30 kHz wide, because it gives voice quality that is comparable to a wired telephone. The transmitter and receiver frequencies of each voice channel are separated by 45 MHZ, to keep them from interfering with each other. Each carrier has 395 voice channels and 21 control channels for activities of registration and paging. Each cell only uses about one-seventh of its frequencies. This helps a hexagonal cell and the six cells in the grid to all use the frequencies. Digital cell phones use the same radio technology in a different way.

For instance, digital phones change voice into binary information (1 and 0) and then compresses it where this compression allows ten digital phones to occupy the same frequency space as one analog cell phone.
Speech is sound in motion, but talking produces acoustic pressure. A telephone reproduces sound by electrical means. However, in wireless technology, a coder inside the mobile telephone converts sound to digital impulses on the transmitting side and on the receiving side it converts these impulses back to analog sounds.

A coder or vocoder is a speech analyzer and synthesizer all in one. A vocoder is found in every digital wireless telephone and is part of a larger chip set called a digital signal processor. In this process, sound gets modeled and transmitted on one end of the vocoder and on the receiving end, the speech synthesizer part, interprets the signal and produces a close match of the original.

These sounds can vary because of telephone circuit’s resistance, while electrically representing speech with a continuous (analog) electromagnetic wave; however, digital signals remain stable for the length of their travel because digital signals are a mathematical or numerical representation of sound, with each sonic nuance captured as a binary number.

On hearing sounds, your ears are responding to tiny, rapid changes in the pressure of the air. These changes are called sound waves. They can have a single frequency and constant amplitude. Hearing is a complex mixture of waves with different frequencies and amplitudes. Sound waves range from pure sine waves to complex combinations of waves. The normal human ear can perceive sound ranging in frequency from 20 to 20,000 Hz.16

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No Network Around ?? Worry Not When There is goTenna !!

goTenna is a cognitive digital radio which is combined with an app that generates its own signal and automatically coordinates with other units within range. It does all the heavy-lifting, and allows one to chat 1-to-1, with a group, or even broadcast openly to anyone nearby.

goTenna uses SMS messaging to provide internet access when there is no 3G or Wi-Fi availability. Where Be-Bound allows users to use email, check the weather and read the news, amongst other functionality, goTenna was developed with more serious applications in mind

The goTenna is targeted for situations where there’s no signal at all. It was born after superstorm Sandy, the 2012 storm that knocked out cell service in parts of New York and New Jersey. In the aftermath, company co-founder Daniela Perdomo, a Brooklyn, N.Y.-based tech entrepreneur originally from São Paulo, wondered if there might be a way to let people still use their smartphones without being susceptible to infrastructure failure. The GoTenna began shipping in October.

Like its name suggests, the goTenna is a radio antenna. The construction of this device goes this way where it is about 6 inches long, it’s small and light enough to clip onto a backpack or jacket—but noticeable enough that people stopped me to ask what it was. It connects via Bluetooth to an Apple or Android phone, where the goTenna app can send and receive data through the antenna when it’s extended to 8 inches. The rechargeable battery lasts about 24 hours, or long enough to send 700 messages.

The goTenna operates on some of the lowest frequencies (151 to 154 MHz) available without a radio license. Those frequencies allow digital signals to travel longer distances. But due to limited bandwidth, goTenna’s technology doesn’t send voice or photos. It only sends text messages and GPS coordinates—sufficient both for telling a buddy you’ve found the perfect campsite…or flagging a helicopter to come get you off that godforsaken mountain.

goTenna’s app is a product of the smartphone age, but the antenna itself is old-school radio. It works best in areas that are mostly flat, or where there is a clear line of sight between both antennas.

goTenna pairs with an iOS or Android device via Bluetooth low energy. Its app will automatically continue to try and send a message until successful and will notify users when a message has been sent. It is possible to send group messages, to send encrypted and “self-destructing” messages to maintain privacy and to “shout” broadcasts to anyone within range.

There are factors that can degrade or block goTenna signals, including glass, large buildings and random urban radio-frequency noise. Even holding it in your hand or attaching it too close to the ground on a backpack can hurt. The app doesn’t let  anyone know when you come in and out of range of another goTenna, just whether a message you’ve sent was received.

goTenna communication, which can be encrypted from end to end, may also appeal to people who want to stay out of regular communication channels—potentially including criminals.

 

 

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